Tone arm



L. BAXTER TONE ARM Lama Bax-far Filed Nov. 28, 1924 ATTORNEY Aug. 14, 1928.

WITNESS: WW0

Patented Aug. 14, 1928.

UNITED STATES LEON BAXTEB, F BROOKLYN, NEW YORK.

TONE ARM.

Application filed November 28, 1924. Serial No. 752,773.

This invention relates to improvements in tone arms for use in connection with phonographs or talking machines.

The principal object of the invention is the provision of a tone arm to which is attached the usual sound box and whereby a loud speaker unit may be added; without necessitating the removal of the sound box when it is desired to utilize a phonograph as a loud speaker for radio reception.

Another object resides in the provision of a tone arm embodying a modifier whereby the volume of sound may be selectively controlled when using the same either for the playing of phonograph records or as a loud speaker.

v With these and other objects in view, the invention resides in certain novel construction and combination and arrangement of parts, the essential features of which are hereinafter fully described, are particularly pointed out in the appended claim, and are illustrated in the accompanying drawing, in which:-

Figure 1 is a side elevation of my improved tone arm.

Figure 2 is atop plan view of the same.

Figure 3 is an end view.

Figure 4 is a longitudinal sectional view on the line H of Figure 2.

Figure 5 is a transverse sectional view on the line 5-5 of Figure 2 showing a sound box and loud speaker unit attached thereto.

Figure 6 is-a detail perspective view of the modifier control.

Referring more particularly to the drawing, the reference numeral 10 designates my improved tone arm in its entirety and which is usually mounted for swinging movement within the cabinet of a phonograph, a portion of the same being illustrated at 11 and which tone arm is in the form of a tubular member 12.

The tubular member 12 is formed with an open end 14, and is provided wi th diametrically opposed ports 15 and *16 arranged at right angle to the axis of said tubular member. Attaching nipples 17 and 18 extend outwardly from the body of the member whereby a sound box 19 and a loud speaker unit 20 may be respectively supported in registration with said ports. It will be noted that thenipple 18 is slightly larger in diameter than the nipple 17 for receiving a sound box of the standard size,

while the loud speaker 20 may be easily inserted over the nipple 17.

For selectively controlling the modulation of the respective instruments, I provide a modifier 21 which is in the form of a sleeve or shell member 22 having its bearing in the open end 14 of the tone arm. The side wall of the sleeve is formed with an opening 23 for registration with the ports in the tone arm, and also with a manipulating head 24 for engagement with the end of the tone arm. For limiting the turning movement of the modulator in opposite directions for bringing the opening 23 in registration with the ports, I provide the sleeve with a slot 25, which receives the end of a screw 26 extending through the tubular member adjacent the free end thereof. The slot is of sufiicient length to permit of approximately one-half revolution of the shell in either direction.

The outer face of the head 24 is provided with suitable indicating indicia 27 for indicating when the slot is in registry with either of the ports.

In practice, it will be seen that both the sound box and the loud speaker unit may be supported simultaneously by the tone arm and the tone of either may be modified by the turning of the head 24 to bring the opening 23 in the sleeve in full or partial registry with either the ports 15 and 16, while the other port is completely closed. It will therefore be seen that the tone may be modulated upon its entrance into the tone arm, thereby eliminating other devices now employed in phonographs for performing this function.

While I have described what I deem to be the most desirable embodiment of my invention, it is obvious that many of the details may be varied without in any way departing from the spirit of my invention, and I therefore do not limit myself to the exact details of construction herein set forth nor to anything less than the whole of my invention limited only by the appended claim.

What is claimed as new is A tone arm comprising a tubular mem-' ber' open at its outer end and having a pair of oppositely disposed nipples provided thereon and constituting a pair of ports in communication with the interior of said tubular member, said nipples adapted to sup port a pair of acoustical instruments, a sleeve rotatably supported in the outer open opening with either of the respective ports upon the limit of turning movement of said sleeve in opposite directions.

In testimony whereof I have afiixed my signature.

LEON BAXTER. 

